In an optical communication system, it is typically necessary to couple an optical fiber to an opto-electronic transmitter, receiver or transceiver device and to, in turn, couple the device to an electronic system such as a switching system or processing system. These connections can be facilitated by modularizing the transceiver device. Various transceiver module configurations are known. For example, the optical transceiver module 10 illustrated in FIG. 1 has a standard configuration or form commonly referred to as a Small Form Factor (SFF) or SFF-Pluggable (SFP) format. Transceiver module 10 includes a metallic module housing 12 in which are housed opto-electronic elements, optical elements, and electronic elements, such as one or more light sources (e.g., lasers), light sensors, lenses and other optics, digital signal driver and receiver circuits, etc. The front end or nose 14 of transceiver module 10 further includes a transmitter receptacle 16 and a receiver receptacle 18 into which optical fiber cables (not shown) are pluggable. The optical cable plug or connector body (not shown) can be of the standard type known as an LC connector, which has a substantially square profile corresponding to the shape of receptacles 16 and 18. Although not shown in FIG. 1 for purposes of clarity, transceiver module 10 can be plugged into a bay in the chassis or cage of an electronic system by inserting the rear end of transceiver module 10 into a bay opening in the cage and latching transceiver module 10 in place. A bail latch 20 facilitates latching transceiver module 10 and, when flipped to an extended position (not shown), serves as a handle by which a person can grip transceiver 10 to extract it from the cage.
Transceiver module cooling is a concern in the art. When transceiver 10 is plugged into a cage bay, the metallic module housing 12 is in contact with metallic walls of the cage bay. The heat emitted by the electronics and opto-electronics in transceiver module 10 in operation is commonly conducted away from transceiver module 10 by the metal walls of the cage bay. Heat sinks can be included in the cage to help dissipate the conducted heat. The cage is commonly mounted within a larger box-like enclosure containing electronics with which the plugged-in transceiver module 10 communicates electrical signals when in operation.